1. Field of the Invention
The present invention relates to a blower used for, for example, an outdoor equipment of an air conditioner, and particularly to its blade structure.
2. Description of Related Art
As a conventional blower realizing high efficiency by improvement of a blade structure, for example, as disclosed in patent document 1, there is a blower which includes an impeller made by radially attaching plural vanes (blades) to the outer periphery of a hub (boss) and in which a specific region extending in a blade span direction is curved to a negative pressure surface side along a trailing edge of the vane over a specified width.
[Patent document 1] JP-A-2003-13892 (paragraphs 20 to 30, FIGS. 1 to 4)
However, in the case where it is curved to the negative pressure surface side along the trailing edge of the blade over the specified width, since the curved portion becomes a resistance to airflow and turbulence occurs, there has been a problem that an increase in input and an increase in noise are caused.